Incremental value of regional wall motion abnormalities for detecting obstructive coronary artery disease by rest-only electrocardiogram-gated single-photon emission computerized tomography myocardial perfusion imaging in suspected coronary artery disease patients.

OBJECTIVE The purpose of this study was to determine whether regional wall motion (WM) abnormalities by rest-only technetium-sestamibi (Tc-MIBI) electrocardiogram (ECG)-gated single-photon emission computerized tomography (SPECT) myocardial perfusion imaging (MPI) had incremental diagnostic value for detecting obstructive coronary artery disease (CAD) in suspected CAD patients. METHODS This study retrospectively studied 255 consecutive suspected CAD patients who underwent rest-only ECG-gated SPECT MPI and were performed coronary angiography within 3 months. Obstructive CAD was defined as ≥70% narrowing of the inner diameter of the left anterior descending coronary artery, left circumflex coronary artery and right coronary artery or their main branches and ≥50% narrowing of the left main coronary artery. QPS and QGS were used to assess rest perfusion and WM. Summed rest score ≥4 and summed motion score ≥2 exhibited in two consecutive segments in one territory was considered abnormal. RESULTS The sensitivity of the combination of perfusion and regional WM abnormalities was significantly higher than perfusion alone for detecting obstructive CAD (46.8% vs. 30.9%; P < 0.001), with similar specificity (91.9% vs. 95.0; P = 0.063). The global chi-square value of combination of perfusion and WM increased from 31.40 to 50.71 (P < 0.001) compared to perfusion. The sensitivity of combination of perfusion and WM for detecting obstructive CAD in patients with multivessel disease was higher than single-vessel disease (56.1% vs. 25.0%; P < 0.001), with similar specificity. CONCLUSION Regional WM abnormalities at rest, as shown by rest-only Tc-MIBI ECG-gated SPECT MPI, have additional diagnostic value over perfusion alone for detecting obstructive CAD in suspected CAD patients.